WebM to MP4

Convert WebM videos to MP4 (H.264) so they play on iPhone, Windows and TVs. Works with screen recordings and downloads. Free, fast and never uploaded.

No upload — 100% private
Instant, on your device
Free, no sign-up
Works offline once loaded

Drop a video to compress or convert

MP4, MOV, WebM, MKV… up to 2 GB — nothing is uploaded

Processed on your device. Nothing is uploaded.

How it works

How to use WebM to MP4

Drop your .webm file — screen recordings, browser captures and downloads all work.
MP4 with H.264 is pre-selected for the widest compatibility.
Click Convert to MP4 and follow the progress bar.
Download the MP4 and share it anywhere.

Why use it

Why use our WebM to MP4 tool

Plays on Apple devices

iPhones, iPads and older Macs often refuse WebM. H.264 MP4 plays natively everywhere.

Audio converted too

Opus audio is converted to AAC where your browser supports it, so the soundtrack plays in every MP4 player.

Hardware-accelerated

Decoding and encoding use your graphics chip through WebCodecs, so conversion is quick even on laptops.

Compress at the same time

Choose 720p or a target size to shrink large screen recordings while converting.

FAQ

Frequently asked questions

Why convert WebM to MP4?

WebM (VP8/VP9 video) is great on the web, but many phones, editors and TVs only accept MP4 with H.264. Converting makes the video universally playable.

Is there quality loss?

WebM to MP4 requires re-encoding the video, but it's done at a high bitrate so the difference is hard to notice. Pick a preset if you want a smaller file instead.

My screen recording has no duration — will it work?

Yes. Browser recordings often lack duration info; the converter scans the file to find it and writes a proper MP4 with a seekable timeline.

How big can the WebM be?

Up to 2 GB. Long recordings take longer and need more memory, so a laptop handles them best.

Is my WebM recording uploaded?

No. Screen and meeting recordings often contain private information, so the WebM is decoded and re-encoded to MP4 entirely on your device. Nothing is sent to a server.

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